For those like me who were fighting with GenMAPP ! Jim, the file seems to be pretty interesting giving for each probe set ID the GB and the prefered GenMAPP one etc... for mostly any kind of chip. pretty useful I think... I ll cross check with my list ! ....see below Dear Dr. Guardiola, We are indeed working an another way to do this. The upcoming version 2 of GenMAPP/MAPPFinder will accept Affymetrix probe set IDs as the primary ID. we hope to release this new version within a couple of months. In the meantime, you can use our converter (http://www.genmapp.org/FAQ.asp#probeset) to convert your Affymetrix IDs into GenBank IDs for use with GenMAPP. If you have problems with this, please let me know and I will do the conversion for you. I apologize for this inconvenience. Regards, Kristina Kristina Hanspers, ME GenMAPP Development Team Bioinformatics Research Associate/Conklin Lab Gladstone Institute of Cardiovascular Disease/UCSF www.GenMAPP.org Ms, Sir, I d like to use GenMapp and MAPPFinfer with my data that come from Affymetrix HU133A GeneChip. Do you have a conversion file already "ready to use" between the Probe set ID of HU133A and the SwissProt ID that could be use for this purpose. It is clear that your software is very exciting but this part of the data processing is compromising its use by a lot of biologists... you have to find another way to do it ! thanks Philippe Guardiola, MD FHCRC, Seattle [[alternative HTML version deleted]]